As electrical power was introduced communities with the formation of the electrical power industry, standards commenced to be developed for distributing and metering equipment both for the convenience of the industry and the safety of the consumer. One such standardization evolved in conjunction with electricity meters. Traditionally, these devices measured the singular electrical parameter, kilowatthours, and were and continue to be fabricated as mechanical devices incorporating inductively rotated disks and mechanically driven readout dials which are read periodically by utility personnel. Positioned on an outside wall surface of a dwelling or commercial facility, the meters typically are supported from a sealed metal enclosure or box within which is mounted a relatively large receiving socket having a plurality of spring-biased jaws in a standardized configuration designed to receive and support the outwardly extending contact blades of a meter base. The meter mechanism is supported from the opposite side of that base and is protected by a clear glass or plastic cover. This cover permits utility personnel to observe the mechanical movement of the meter components, thus providing a modicum of assurance as to their performance. To provide for safety, the metering components traditionally have incorporated lightning arresters and the entire installation is coupled with a conductive path including the socket and the metal enclosures extending to earth ground.
As metering technology has advanced, devices providing mechanically derived single parameter outputs, such as kilowatthours, are being supplanted by more advanced, solid-state electronic meters providing multi-parameter outputs both as visual readouts and as electrical signals which are transmissible to centralized data collection and treatment facilities. The multi-function output meters are particularly desired by industrial consumers, as well as the utilities and provide a sequence of outputs, for example, as a timed scrolling arrangement developing a broad range of parameter information. Of the parameters industry will select, for example, are watthour, varhour, Qhour, volt.sup.2 hour, volthour, ampere.sup.2 hour, amperehour, and volt amperes. Additionally, watt, var, Q, ampere, and volt functions may be utilized in a variety of combinations. In this regard, reference is made to U.S. Pat. No. 4,615,009 by Battocletti and Hammond, entitled "Electronic Energy and Power Monitoring Apparatus", issued Sept. 30, 1986.
Notwithstanding the significantly enhanced performance and expanded measurement capabilities of modern metering systems, such systems still are called upon to conform to the standardized earlier packaging and mounting procedures, both to assure a desirable universality and for reasons of power distribution safety. Thus, the modern electronic meter is mounted upon the large blade and jaw socket and is packaged in a clear glass or plastic cover extending from the sealed metal mounting box coupled to earth ground. Such packaging is not conducive to solid-state circuitry. Accepted materials for which the socket-meter structures are fabricated conventionally are black thermosetting plastics selected for strength, dielectric characteristics and flame retardation function. However, the materials so elected from requirements of the past also contribute to the development of heat within the clear enclosures which, when protecting mechanical metering produce no adverse effect. On the other hand such elevated temperatures adversely affect meters employing solid-state circuit components. Particularly where such components as EPROMS are employed, which is often the case, ultra-violet radiation also will have an adverse effect on the circuits over the long term. Additionally, such circuits become vulnerable to the effects of electromagnetic interference (EMI) and radio frequency interference (RFI) and, in some cases, will be seen to generate RFI types of noise where the circuits are digital in function. For example, where digital phase shifting and/or correction is carried out as described in U.S. Pat. No. 4,408,283, clock frequencies of about 11 megaHertz will be employed which may constitute a form of RFI without proper shielding.
In part because of the larger electrical parameter measurement capabilities of solid-state circuit meters, it is desirable to provide switching access to them on the part of utility personnel without disturbing the integrity of the meter seal formed by the cover and mounting box. In the past, such access has been achieved with levers and the like which were in one manner or another extensible through the glass cover structure, with security provided by keys or the like. Modern solid-state meter structures, however, require additional inputs of this hand actuable nature. For example, it is desirable to develop a form of control over the scrolled outputs of liquid crystal display (LCD) readouts and the like such that they can be stopped or "rewound" to an initial readout. Difficulties of meter handling also arise in adapting old, standardized, encasing techniques to modern electronics. Typical utility personnel are not familiar with the multi-pin connectors of digital-data conveyance systems and similar very delicate structures. As a consequence, when such couplings and the like are combined with the relative massive socket structures and the outdoor environment of a meter, damage to the former is often the result of meter changing procedures and the like.